ADAPTIVE CATEGORICAL LOUDNESS SCALING (ACALOS)
Psychoacoustic measurement method for recording individual, subjective loudness perception.
In loudness scaling, test signals of different levels are presented. The test person is asked to rate the subjectively perceived loudness of the signal on a given categorical scale representing the units from "not heard", "very quiet", "quiet", "medium", "loud", "very loud" to "too loud". The verbal scale is mapped to numerical values between 0 ("not heard") and 50 ("too loud") and plotted as a function of the level of the test signal. In the audiogram display, the so-called auditory field, curves of equal loudness are then plotted against the level.
Advantages and areas of application
- Diagnostics of hearing disorders
- Recording of the recruitment phenomenon for differential diagnosis of sensorineural hearing loss
- Determination of fitting parameters for dynamic-compression hearing aids as well as for cochlear implants
- Verification of the fitting success of hearing aids as well as cochlear implants
Narrowband noise of different center frequencies as well as broadband signals like speech simulating noise can be used as test signals.
- Third-octave noise for narrowband loudness scaling up to 10 kHz
- Representation of the auditory dynamic range in the auditory field by means of curves of equal loudness for all frequencies
- Speech simulating noise for broadband loudness scaling
- Automatic, adaptive loudness scaling according to DIN EN ISO 16832
- Early, manual end of a measurement possible
- Various model functions for adapting loudness curves to the measured values possible
- Manually adjustable loudness scaling possible
- Measurement with response input by patient possible
Under "R&D" you can download the R&D version of the measurement procedure as well as a free 30-day test license. The CE-certified version can be obtained from your audiometer manufacturer.